Internal-combustion engine



W. R. CUMMINS.

INTERNAL COMBUSTION ENG INE.

APPLICATION FILED Nov.2o. I9IB.

1 4m 1 u Patented July 6, 1920.

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w F F M x Q rIl/l l/ I I o w in O D l/ ,0 O O O o o O D O O O S b o u pm 0 o W o 3/ O O O WILLIAM RUSSELL OUMMINS, 0F GLASGOW, SCOTLAND.

INTERNALGOMBUSTION ENGINE.

Specification of Letters Patent.

Patented July 6, 19236 Application filed November 20, 1918. Serial No. eeaaes.

Contains, a subject of the King of Great Britain and Ireland, and of 1 Grosvenor Terrace, Hillhead, Glasgow, Scotland, have invented new anduseful Improvements in Internal-Combustion Engines, of which the following is a specification.

This invention refers to two stroke cycle internal combustion engines of the. type comprising a power cylinder, an auxiliary cylinder extending outwardly from, of greater diameter than and coaxial wlth the power cylinder, a cylindrical guide Within the auxiliary cylinder co-axial therewith, a connecting rod crosshead fitting within and adapted to reciprocate in the guide, a piston for the power' cylinder connected to the crosshead, and an annular piston for the auxiliary cylinder connected to the power piston by a tubular sleeve, so arranged that as the power piston reciprocates, the outward movement of the auxiliary piston produces a suction stroke in the annular space contained between the walls of the auxiliary cylinder and the tubular sleeve due to the piston moving away from the inner end of the auxiliary cylinder, and the inward movement produces a compression stroke, the ef-. 1 I fects of which, are used for scavenging or delivering supplies of combustible mixture to the power cylinder.

The object of this invention is to make provision in engines of this type for causing a substantial quantity of air to be circulated in the region about the outer face of the power piston for cooling purposes, and in some cases also to obtain cushioning efl ects.

In constructing a two stroke cycle internal combustion engine according to this invention, the outer end of the annular space, contained between the walls of the auxiliary cylinder and the cylindrical guide for the crosshead, is close. to form a circulation chamber, a hollow trunk is provided to connect the crosshead with the power piston, ports are formed extending through the walls of the trunk in the region about the outer face of the power piston and a pas,- sage is formed extending between the walls of the tubular sleeve (which connects the power piston with the auxiliary piston) and the trunk, so that as the power piston reciprocates, the outward movement of the auxiliary piston produces a compression stroke in the circulation chamber due to its movwardly from the power E the piston of the mg toward the outer end of the chamber, and the inward movement a suction stroke, whereby air 1s caused to be circulated in the region about the outer face of the power piston. 4

Some examples of construction according to this invention will now be described with reference to the accompanying drawings, in which Figures 1, 2 and 3 are longitudinal sections illustrating constructions embodying various modifications. Fig. 4 is-a longitudinal section showing a portion of a power piston with associated parts.

In the drawings, A designates the power cylinder of the engine, 13 the auxiliary cylinder of greater diameter i hich extends outcylinder, C the cylindrical guide Within the auxiliary cylinder, I) the connecting rod crosshead fitting within and adapted toreciprocate in the guide, power cylinder, and F the annular piston of the auxiliary cylinder which is connected to the power piston by a tubular sleeve G. In the operation of engines of the type defined, the outward movement of the auxiliary piston F produces a suction stroke in the annular space contained between the walls of the auxiliary cyllnder B and the tubular sleeve G due to its movlng away from the inner end of the cylinder B, and the inward movement produces a compression stroke for the purpose of scavenging or delivering supplies of combustible mixture to the power cylinder A, as is well understood.

The improvements according to this invention consist as exemplified in the constructions illustrated in providing means, such as the cover H, for closing the outer end of the annular space contained between the walls of the auxiliary cylinder B and the cylindrical guide C in order to form a circulation chamber, the provision of a hollow trunk, such as J, connecting the crosshead D with the power piston E, ports, such as K. extending through the walls of the trunk J in the region about the outer face of the power piston E, and a passage, such as T1, extending between the walls of the tubular sleeve G and the trunk J, whereby as the engine operates the outward movement of the auxiliary piston F produces a compression stroke in the circulation chamber due to its moving toward the outer end of the chamber causing air to be expelled therersaaeii from and to pass through the passage I1 to the ports K into the hollow interior of the trunk J, and in so doing circulate in the region about the outer face of the power piston E and the inward movement of the auxiliary piston F produces (urculatlon of air in the reverse direction.

As shown at Figs. 1. and 2, deflectors such as M may be provided for directing the air against the outer face of the power piston, and in order to increase the cooling surface, parts projecting from the outer face of the power piston, such as ribs N, see Fig. 1, or

- heat conductors N, see Fig. 3, may be provided. These conductors N, as shown at Fig. 4, may consist of open ended tubes projecting from the outer face of the piston E.

In the construction shown at Fig. 1, the outer end of the trunk J is open, in which case air may circulate freely into and out of the trunk so that the air used is constantly changing. W'th this arrangement no appreciable cushioning effect would be obtained.

In the constructions shown at Figs. 2 and 3, the outer end of the trunk is closed by a partition J in which case the circulation produced is of the air inclosed within the circulation chamber, the passage L, and the interior of the trunk J. With this arrangement a cushioning effect is produced by the air compressed in the circulation chamber as the piston F completes its outward stroke. As the extent to which the inclosed air is circulated depends partly upon the clearance in the circulation chamber and the area of the passage L, these may be reduced as far as practicable. The air used under these conditions, and, if desired, in constructions such as illustrated at Fig. 1, may be cooled within the circulation chamber by providing means through which a cooling medium is adapted to be circulated. For instance,-

the cylindrical guide C may be surrounded by a coil P, see Fig. 2, or by a jacket P see Fig. 3. Further, the passage L may be furnished with ribs R, see Fig. 3, extending from the walls of the tubular sleeve G for the transference of heat.

I claim:

1. A two stroke cycle internal combustion engine of the type defined, comprising an auxiliary cylinder, a power piston, a cylindrical cross-head guide, an annular piston in said auxiliary cylinder, a tubular sleeve connecting said annular piston and power piston and having in combination a circulation chamber contained between the walls of the auxiliary cylinder and the cylindrical guide for the crosshead closed at its outer end, a hollow trunk connecting the crosshead with the power piston, ports extending through the walls of the trunk in the region about the outer face of the power piston, deflectors within the hollow interior of the trunk, and

a passage extending between the walls of the tubular sleeve and the trunk, for the purposes set forth.

2. A two stroke cycle internal combustion engine of the type defined, comprising an auxiliary cylinder, a power piston, a cylindrical cross-head guide, an annular piston in said auxiliary cylinder, a tubular sleeve connecting said annular piston and power piston and having in combination a circulation chamber contained between the walls of the auxiliary cylinder and the cylindrical guide for the crosshead closed at its outer end, a hollow trunk connecting the crosshead with the power piston, ports extending through the walls of the trunk in the region about the outer face of the power piston, parts projecting from the outer face of the power piston, and a passage extending between the walls of the tubular sleeve and the trunk, for the purposes set forth.

3. A. two stroke cycle internal combustion engine of the type defined, comprising an auxiliary cylinder, a power piston, a cylindrical cross-head guide, an annular piston in said auxiliary cylinder, a tubular sleeve connecting said annular piston and power piston and having in combination a circulation chamber contained between the walls of the auxiliary cylinder and the cylindrical guide for the crosshead closed at its outer end, a hollow trunk connecting the crosshead with the power piston, ports extending through the walls of the trunk in the region about the outer face of the power piston, open ended tubes projecting from the outer face of the power iston, and a passage extending between t e Walls of the tubular sleeve and the trunk, for the purposes set forth.

4. A two stroke cycle internal combustion engine of the type defined, comprising an auxiliary cylinder, a power piston, a cylindrical cross-head guide, an annular piston in said auxiliary cylinder, a tubular sleeve connecting said annular piston and power piston and having in combination a circulation chamber contained between the walls of the auxiliary cylinder and the cylindrical guide for the crosshead closed at its outer end, a hollow trunk closed at its outer end connecting the crosshead with the power piston, ports extending through the walls of the trunk in the region about the outer face of the power piston, and a passage extending between the walls of the tubular sleeve and the trunk, for the purposes set forth.

5. A two stroke cycle internal combustion engine of the type defined, comprising an auxiliary cylinder, a power piston, a cylindrical cross-head guide, an annular piston in said auxiliary cylinder, a tubular sleeve connecting said annular piston and power piston and having in combination a circulation chamber contained between the walls of the auxiliary cylinder and the cylindrical guide for the crosshead closed at its outer end, a hollow trunk connecting the crosshead with the power piston, a partition at the outer end of the trunk, ports extending through the walls of the trunk in the region about the outer face of the power piston, deflectors within the hollow interior-of the trunk, and a passage extending between the walls of the tubular sleeve and the trunk, for the purposes set forth.

(5. A two stroke cycle internal combustion engine. of the type defined, comprising an auxiliary cylinder, a power piston, a cylindrical cross-head guide, an annular piston in said auxiliary cylinder, a tubular sleeve connecting said annular piston and power piston and having in combination a circulation chamber contained between the walls of the auxiliary cylinder and the cylindrical guide for the crosshead closed at its outer end, a hollow trunk connecting the crosshead with the power piston, a partition at the outer end of the trunk, ports extending through the walls of the trunk in the region about the outer face of the power piston, parts projecting from the outer face of the power piston, and a passage extending between the walls of the tubular sleeve and the trunk, for the purposes set forth.

7. A two stroke cycle internal combustion engine of the type defined, comprising an auxiliary cylinder, :1 power piston, a cylindrical cross-head guide, an annular piston in said auxiliary cylinder, a tubular sleeve connecting said annular piston and power piston and having in combination a circulation chamber contained between the walls of the auxiliary cylinder and the cylindrical guide for the crosshead closed at its outer end, a hollow trunk connecting the crosshead with the power piston, apartition at the outer end of the trunk, ports extending through the walls of the trunk in the region about the outer face of the power piston, open ended tubes projecting from the outer face of the power piston, and a passage extending between the walls of the tubular sleeve and the trunk, for the purposes set forth.

8. A two stroke cycle internal combustion engine of the type defined, comprising an auxiliary cylinder, a power piston, a cylindrical cross-head guide, an annular piston in said auxiliary cylinder, a tubular sleeve connecting said annular piston and power piston and having in combination a circulation chamber contained between the walls of the auxiliary cylinder and the cylindrical guide for the crosshead closed at its outer end, means within the circulation chamber through which a cooling medium is adapted to be circulated, a hollow trunk connecting the crosshead with the power piston, ports extending through the walls of the trunk in the region about the outer face of the power piston, and a passage extending between the walls of the tubular sleeve and the trunk, for the purposes set forth.

9. A two stroke cycle internal combustion engine of the type defined, comprising an auxiliary cylinder, a power piston, a cylindrical cross-head guide, an annular piston in said auxiliary cylinder, a tubular sleeve connecting said annular piston and power piston and having in combination a circulasage extending between the walls of the tu bular sleeve and the trunk, for the purposes set forth.

1(). A two-stroke cycle internal combustion eng ne, comprising a power cylinder, a power piston movable in said power cylinder, an auxiliary cylinder extending outwardly from said power cylinder, said auxiliary cylinder coaxial with and of greater diameter than said power cylinder, an annular piston movable in said auxiliary cylinder, a tubular sleeve connecting said power piston and said annular piston, a cylindrical guide within said auxiliary cylinder coaxial therewith, said guide spaced radially from said auxiliary cylinder to afford between the walls of said guide and said auxiliary cylinder a circulation chamber closed at its outer end, a cross-head movable in said guide, a hollow trunk connecting saidpower piston and said cross-head, said trunk spaced radially from said sleeve to afford between the walls of said trunk and said sleeve a passage communicating with said chamber, said trunk formed with through ports in the region about the outer face of said power piston, and deflectors within said trunk.

11. A two-stroke cycle internal combus tion engine, comprising a power cylinder, a power piston movable in said power cylinder, an auxiliary cylinder extending outwardly from said power cylinder, said auxiliary cylinder coaxial with and of greater diameter than said power cylinder, an annular piston movable in said auxiliary cylinder, a tubular sleeve connecting said power piston and said annular piston, a cylindrical guide within said auxiliary cylinder coaxial therewith, said guide spaced radially from said auxiliary cylinder to afford between the walls of said guide and said auxiliary cylinder a circulation chamber closed at its outer end, a cross-head movable in said ports in the region about the outer face of said power piston, and parts projecting from the outer face of said power piston.

. radially from said ford between the walls of said guide and 12. A two-stroke cycle internal combustion engine, comprising a power cylinder, a

power piston movable in said power cylinder, an auxlliary cylinder extending outwardly from said power cylinder, said auxiliary cylinder coaxial with and of greater diameter than said power cylinder, an annular piston movable in said auxiliary cylinder, a tubular sleeve connecting said power piston and said annular piston, a cylindrical guide within said auxiliary cylinder coaxial therewith, said guide spaced auxiliary cylinder to afsaid auxiliary cylinder a circulation chamber closed at its outer end, across-head movable in said guide, a hollow trunk connecting said power piston and said crosshead, said trunk spaced radially from said sleeve to aiiord between the walls of said trunk and said sleeve a passage communieating with said circulating chamber, said trunk formed with through ports in the region about the outer face of: said power piston and tubes projecting from the outer face of said power piston.

- 13. A two-stroke cycle internal combustion engine, comprising a power cylinder, a power piston movable in said power cylinder, an auxiliary cylinder extending outwardly from said power cylinder, said auxiliary cylinder coaxial with and of. greater diameter than said power cylinder, an annular piston movable in said auxiliary cylinder, a tubular sleeve connecting said power piston and said annular piston, a cylindrical guide within said auxiliary cylinder coaxial therewith, said guide spaced radially from said auxiliary cylinder tr afi'ord between the walls of said guide and said auxiliary cylinder a circulation chamber closed at its outer end, a cross-head movable in said guide, and a hollow trunk closed at its outer end, said trunk connecting said power piston and said cross-head, said trunk spaced radially from said sleeve to afford between the walls of said trunk and said sleeve a passage communicating with said chamber, said trunk formed with through ports in the region about the outer face of said power piston.

14. A two-stroke cycle internal combustion engine, comprising a power cylinder, a power piston movable in said power cylinder, an auxiliary cylinder extending outwardly from said power cylinder, said auxiliary cylinder coaxial with and of greater cylindrical guide within said auxiliary cylinder coaxial therewith, said guide spaced radially from said auxiliary cylinder to afford between the walls of said guide and said auxiliary cylinder a circulation cham: ber closed at its outer end, a cross-head movable in said guide, a hollow trunk connecting said power piston and said crosshead, said trunk spaced radially from said sleeve to afford between the walls of said trunk and said sleeve a passage communieating with said OllilIIlbGIy said trunk formed with through orts in the region about the outer face or said power piston, and a partition at the outer end of said trunk.

15. A two-stroke cycle internal combustion engine, comprising a power cylinder, a power piston movable in said power cylinder, an auxiliary cylinder extending outwardly from said power cylinder, said auxiliary cylinder coaxial with and of greater diameter than said power cylinder, an annular piston movable in said auxiliary cylinder, a tubular sleeve connecting said power piston and said annular piston, a cylindrical guide within said auxiliary cylinder coaxial therewith, said guide spaced radially from said auxiliary cylinder to afford between the walls of said guide and said auxiliary cylinder a circulation chamber closed at its outer end, a cross-head movable in said guide, a hollow trunk connecting said power piston and said cross-head, said trunk spaced radially from said sleeve to afford between the walls of said trunk and said sleeve a passage communicating with said chamber, said trunk formed with through ports in the region about the outer face of said power piston, a partition at the outer end of said trunk, and parts projecting from the outer face of said power piston.

16. A two-stroke cycle internal combustion engine, comprising a power cylinder, a power piston movable in said power cylinder, an auxiliary cylinder extending outwardly from said power cylinder, said auxiliary cylinder coaxial with and of greater diameter than said power cylinder, an annular piston movable in said auxiliary cylinder, a tubular sleeve connecting said power piston and said annular piston, a cylindrical guide within said auxiliary cylinder coaxial therewith, said guide spaced radially from said auxiliary cylinder to atford between the walls ofsaid guide and said auxiliary cylinder a circulation chamber closed at its outer end, a cross-head movable in said guide, a hollow trunk connecting said power piston and said cross-head,

said trunk spaced radially from said sleeve to afford between the walls of said trunk and said sleeve a passage communicating with said chamber said trunk formed with through ports in the region about the outer face of said power piston, a partition at the outer end of said trunk, and tubes projecting from the outer face of said power piston.

17. A two-stroke cycle internal combustion engine, comprising a power cylinder, a power piston movable in said power cylinder, an auxiliary cylinder extending outwardly from said power cylinder, said auxiliary cylinder coaxial with and of greater diameter than said power cylinder, an annular piston movable in said auxiliary cylinder, a tubular sleeve connecting said power piston and said annular piston, a cylindrical guide within said auxiliary cylinder coaxial therewith, said guide spaced radially from said auxiliary cylinder to afford between the walls of said guide and said auxiliary cylinder a circulation chamber closed at its outer end, means within said circulation chamber through which cooling medium may be circulated, a cross-head movable in said guide, and a hollow trunk connecting said power piston and said cross-head, said trunk spaced radially from said sleeve to afford between the walls of said trunk and said sleeve a passage communicating with said chamber, said trunk formed with through ports in the region about the outer face of said power piston.

18. A two-stroke cycle internal combustion engine, comprising a power cylinder, :1 power piston movable in said power cylinder, an auxiliary cylinder extending outwardly from said power cylinder, said auxiliary cylinder coaxial with and of greater diameter than said power cylinder, an annular piston movable in said auxiliary cylinder, a tubular sleeve connecting said power piston and said annular piston, a cylindrical guide within said auxiliary cylinder coaxial therewith, said guide spaced radially from saidauxiliary cylinder to aflord between the walls of said guide and said auxiliary cylinder a circulation chamber closed at its outer end, a cross-head movable in said guide, a hollow trunk closed at its outer end, said trunk connecting said power piston and said crosshead, said trunk spaced radially from said sleeve to afford between the walls of said tninkand said sleeve a passage communicating with said chamber, said trunk formed with through ports in the region about the outer face of said power piston, and means in the path of the medium flowing through said chamber and passage for cooling said medium.

19. In a two-stroke cycle internal combustion engine, in combination with a power cylinder, a power piston reciprocable in said cylinder, a scavenging pump cylinder c0- axial with said power cylinder, a cover closing the front end of said pump cylinder, a scayenging piston reciprocable in said pump cylinder, a cross-head, a cylindrical guide for said cross-head, said guide extending from said cover into said pump cylinder and coaxial with said cylinders, and tubular members connecting said power piston with said scavenging piston and said power piston wlth said cross-head, said tubular members being coaxial with said cylinders and presenting between them an annular passage, the tubular member connecting said power piston with said cross-head being formed with ports located in the region about the outer face of said power piston and aiiording communication between the interior of said last named tubular member and said passage, whereby on the reciprocation of said scavenging piston air is caused to be circulated in the region about the outer face of said power piston.

20 In a two-stroke cycle internal combustlon engine, in combination with a power cylinder, a power piston reciprocable in said cylinder, a scavenging pump cylinder coaxial with said power cylinder, a cover closing the front end of said pump cylinder, a scavenging piston reciprocable in said pump cylinder, a cross-head, a cylindrical guide for said cross-head, said guide extending from said cover into said pump cylinder and coaxial with said cylinders, and tubular members connecting said power piston with said scavenging piston and said power pis- 100 ton with said cross-head, said tubular members being coaxial with said cylinders and presenting between them an annular passage, the tubular member connecting said power piston with said cross-head being 105 closed at its outer end and formed with ports located in the region about the outer face of said power piston and afi'ording communication between the interior of said last named tubular member and said passage, whereby on the reciprocation of said scavenging piston air is caused to be circulated in the region about the outer face of said power piston.

21. A two-stroke cycle internal combus- 115 tion engine, comprising a power cylinder,

a power piston movable in said power cylinder, an auxiliary cylinder extending outwardly from said power cylinder, said auxiliary cylinder coaxial with and of greater diameter than said power cylinder, an annular piston movable in said auxiliary cylinder, a tubular sleeve connecting said power piston and said annular piston, a cylindrical guide within said auxiliary 125 cylinder coaxial therewith, said guide spaced radially from said auxiliary cylinder to afford between the walls of said guide and said auxiliary cylinder, a circulation chamb r losed at its outer end, a cross-head m0v- 3 able in said guide, a hollow trunk connecting said power piston and said cross-head, said trunk spaced radially from said sleeve to afford between the walls of said trunk and said sleeve a passage communicating with said chamber, said trunk formed with through ports in the region about the outer face of said power piston, and means applied to said power piston to increase the heat dissipating surface thereof.

22. A two-stroke cycle internal combustion engine, comprising a power cylinder, a power piston movable in said power cylinder, an auxiliary cylinder extending outwardly from said power cylinder, said auxiliary cylinder coaxial with and of greater diameter than said power cylinder, an annular piston movable in said auxiliary cylinder, a tubular sleeve connecting said power ieaaeii piston and said annular piston, a cylindrical guide within said auxiliary cylinder coaxial therewith, said guide spaced radially from said auxiliary cylinder to afford between the walls of said uide and said auxiliary cylinder a circulation chamber closed at its outer end, a cross-head movable in said.

guide, a hollow trunk connecting said power piston and said cross-head, said trunk spaced radially from said sleeve to afford between the walls of said trunk and said sleeve a passage communicating with said chamber, said trunk formed with through ports in the region about the outer face of said power piston, and means to extract heat from the air circulated through said chamber and said passage WILLIAM RUSSELL CUMMINS. 

